Code tidy up

- remove non-null assertion
- fix english typos

projects/app/src/client/ui/auth.ts

@@ -57,7 +57,7 @@ type AuthApi = {
   signOut: () => void;
 };
 
-// TODO: how to handle beind anonymous then logging in but there's an existing
+// TODO: how to handle being anonymous then logging in but there's an existing
 // user. It's more like "switch user" than it is anything else. Maybe even in
 // the anonymous case you should have to give your name? Only after you actually
 // save some useful state.

projects/app/src/client/ui/replicacheOptions.web.ts

@@ -1,6 +1,6 @@
 import { ReplicacheOptions } from "replicache";
 
-// Intentionally DO NOT allow Expo top inline the environment variable,
+// Intentionally DO NOT allow Expo to inline the environment variable,
 // otherwise it will leak into the browser bundle otherwise the browser code
 // will also think it's in static render mode and use the
 // ExperimentalMemKVStore.